<HTML><HEAD><TITLE>?Element `-@ ?SetVariable</TITLE>
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<H1>?Element `-@ ?SetVariable</H1>
Set non-membership constraint
<DL>
<DT><EM>SetVariable</EM></DT>
<DD>A set variable.
</DD>
<DT><EM>Element</EM></DT>
<DD>A ground term or a variable.
</DD>
</DL>
<H2>Description</H2>
Constrain SetVariable to not include Element.<P>
		If Element is a variable then the constraint
		is suspended until it becomes ground.
<H3>Fail Conditions</H3>
Fails if Element must be a member of SetVariable.
<H3>Resatisfiable</H3>
No.
<H2>Examples</H2>
<PRE>
?- S `:: []..[a,b], a `-@ S, glb_poss(S,G,P).
G = [], P = [b]

?- S `:: [c]+[a,b], c `-@ S.
no

?- S `:: [a]+[b,c], z `-@ S, glb_poss(S,G,P).
G = [a], P = [b,c]

?- S `:: []..[a,b], X `-@ S, glb_poss(S,G,P).
G = [], P = [a,b]

?- S `:: []..[a,b], X `-@ S, X=b, glb_poss(S,G,P).
G = [], P = [a]
</PRE>
<H2>See Also</H2>
<A HREF="../../lib_public/cardinal/BA-2.html">`@ / 2</A>, <A HREF="../../lib_public/cardinal/in-2.html">in / 2</A>, <A HREF="../../lib_public/cardinal/notin-2.html">notin / 2</A>, <A HREF="../../lib_public/cardinal/BNN-2.html">`:: / 2</A>
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